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Bradley R. Frieberg, Peter F. Green, Emmanouil Glynos
Applications of polymer thin films range from active and passive coatings to flexible electronics and energy conversion. During the last decade substantial efforts have been devoted toward understanding the physical properties of polymer thin films, where
Vladimir P. Oleshko, Jenny J. Kim, Jennifer L. Schaefer, Steven D. Hudson, Christopher L. Soles, Adam Simmonds, Jared Griebel, Kookheon Char, Jeff Pyun
Poly(sulfur-random-(1,3-diisopropenylbenzene) (poly(S-r-DIB)) copolymers synthesized via inverse vulcanization form high molecular mass electrochemically active polymers capable of realizing enhanced capacity retention (1005 mAh/g at 100 cycles) and
Fan Zhang, Ivan Javni, Olivera Bili?, Nikola Bili? , Zoran S. Petrovic, Jan Ilavsky
Isosorbide, a renewable diol derived from starch, was used in combination with butane diol or alone as the chain extender in two series of thermoplastic polyurethanes with 50 and 70% soft segment concentration (SSC). Polyurethanes with 50% SSC based on
Kirt A. Page, Jae W. Shin, Scott Eastman, Brandon W. Rowe, Sangcheol Kim, Ahmet Kusoglu, Kevin G. Yager, Gery R. Stafford
Perfluorinated ionomers, in particular Nafion, are an essential component in hydrogen fuel cells, as both the proton exchange membrane and the binder within the catalyst layer. During normal operation of a hydrogen fuel cell the ionomer will progressively
Nanostructured, responsive hydrogels composed of oppositely charged triblock copolymers with charged end-blocks and neutral, hydrophilic mid-blocks in aqueous solution were recently discovered. Due to electrostatic interactions, the end-blocks microphase
Brian G. Bush, Jenna M. Shapiro, Frank W. DelRio, Robert F. Cook, Michelle L. Oyen
Colloidal-probe spherical indentation load-relaxation experiments are conducted on poly(ethylene glycol) (PEG) hydrogel materials to quantify the steady-state mechanical properties and time-dependent transport properties in a single experiment. A probe
James A. Warren, David Saylor, Christopher Forrey, Changsoo Kim
An overview of diff use interface models specific to drug eluting stent coatings is presented. Microscale heterogeneities, both in the coating and use environment, dictate the performance of these coatings. Using diffuse interface methods, these
Bharath NMN Natarajan, Noa Lachman, Thomas F. Lam, Douglas Jacobs, Christian J. Long, Minhua Zhao, Brian L. Wardle, Renu Sharma, James A. Liddle
Carbon nanotube (CNT) reinforced polymers are next-generation, high-performance, multifunctional materials with a wide array of promising applications. The successful introduction of such materials is hampered by the lack of a quantitative understanding of
Fan Zhang, Ivan Javni, Olivera Bili?, Nikola Bili? , Zoran S. Petrovic, Jan Ilavsky
Isosorbide, a cyclic, rigid and renewable diol was used as a chain extender in two series of thermoplastic polyurethanes. Isosorbide was used in combination with butane diol or alone to examine the effects on polyurethane morphology. Two series of
Kalman D. Migler, Angela R. Hight Walker, Anthony P. Kotula
The kinetic pathway by which a molten polymer transforms into a multi-length scale semi-crystalline structure upon cooling is an unsolved problem in polymer physics, yet it is critical to the processing, properties and ultimate performance of these
Small angle X-ray scattering (SAXS) is a powerful technique that is used to resolve the size and structure of phases on the nanometer scale, within a sample. While these features may also be observed with other techniques, such as: electron microscopy or
Jae Hyun Kim, Nathanael A. Heckert, Kai-Li Kang, Walter G. McDonough, Kirk D. Rice, Gale A. Holmes
High strength polymer fibers such as poly(p-phenylene terephalamide) (PPTA) are used for ballistic body armors. Additionally, a co-polymer aramid fiber containing 5-amino-2-(p-aminophenyl)-benzimidazole is also being considered as reinforcement for
Edward Garboczi, Aaron Forster, Jan Miller, Chen-Luh Lin, Cesar Chan, Kumar Natesaiyer, David Song, Suman Sinha-Ray
A combined computational/experimental materials science technique was developed for acquiring the structure of a rigid organic foam (ROHACELL) using X-ray computed tomography with appropriate image analysis, computing the elastic moduli using large-scale
Amit Vaish, David J. Vanderah, Lee J. Richter, Michael Dimitriou, Kristen L. Steffens, Marlon L. Walker
We present a facile strategy to modify poly(dopamine)(PDA)-coated substrates. Using thiol-terminated short chain ethylene oxide oligomers (OEG) under aqueous conditions, we explore the creation of a model surface exhibiting resistance to nonspecific
There is a need to design new materials to achieve smaller pitches and reduced interfacial widths for use in the nanopatterning of block copolymers (BCPs). One option is the use of blends, where the addition of a homopolymer which selectively associates to
Minhua Zhao, Bin Ming, Jae-Woo Kim, Luke J. Gibbons, Xiaohong Gu, Tinh Nguyen, Cheol Park, Peter T. Lillehei, John S. Villarrubia, Andras Vladar, James A. Liddle
Despite many studies of subsurface imaging of carbon nanotube (CNT)-polymer composites via scanning electron microscopy (SEM), significant controversy exists concerning the imaging depth and contrast mechanisms. We studied CNT-polyimide composites and, by
Nichole Nadermann, Edwin P. Chan, Christopher M. Stafford
We study the water transport and swelling properties of an ultrathin polyamide selective layer with a hydroxyl-rich polymer coating, i.e., a polymer bilayer, using quartz crystal microbalance with dissipation (QCM-D). Specifically, we use QCM-D to measure
Lee J. Richter, Regis J. Kline, Hyun Wook Ro, Chad R. Snyder, Andrew A. Herzing, Sebastian Engmann
A consensus is emerging that every phase present in a bulk heterojunction organic photovoltaic (OPV) device is not material pure. In general, there will exist at least one region characterized by a mixture of donor and acceptor. Significant insights into
Alexander Peterson, Michael Halter, Alessandro Tona, Anne Plant
Background Surface plasmon resonance imaging (SPRI) is a label-free technique that can image refractive index changes at an interface. We have previously shown that SPRI can be used to study the dynamics of cell-substratum interactions. However
In recent years, hundreds of scientific studies have been published regarding gecko-inspired adhesives. The primary reason for this increasing interest lies in the unique properties which are combined in the adhesive system of the gecko: this natural
The objective of this study was to investigate how the heterogeneity due to nanoparticle dispersion of polymeric coatings affects surface morphological changes during ultraviolet (UV) exposure under different weathering conditions. Three types of nano
Jeanice M. Brown Thomas, Margaret C. Kline, Katherine E. Sharpless, S A. Margolis
The National Institute of Standards and Technology coordinates the Micronutrients Measurement Quality Assurance Program (MMQAP) for laboratories that measure fat- and water-soluble vitamins and carotenoids in human serum and plasma. This report describes
Christopher Forrey, D M. Saylor, Joshua S. Silverstein, Jack F. Douglas, Eric Davis, Yossef A. Elabd
Diffusion of small to medium sized molecules in polymeric medical device materials underlies a broad range of public health concerns related to unintended leaching from or uptake into implantable medical devices. Knowledge of diffusion rates is thus
Cellular behavior can be influenced by the chemical and physical surface characteristics of biomedical substrates. To understand the relationships between various topographical surface patterns and cellular activities, various types of pattern models have
Aaron Forster, Emilien J. Guigues, Amanda Forster, Jeffrey M. Davis, Kirk D. Rice
A laminate foam composite is recommended in the National Institute of Justice (NIJ) 0115.00 standard as the backing material for testing stab resistant body armor. The foam specification originated from early work to match force-displacement profiles from